iOS tries to prevent you from installing apps on your iPad and iPhone that won’t run, but sometimes you’re left with cruft—digital vestiges of the past—that persist and make things difficult for you to sort out what’s wrong.

That appears to have happened to Macworld reader Carol, who has an app called Life Cycle installed on her iPad. The update badge is on her App Store icon, but whenever she tries to install the update, she’s told it’s not compatible with iPad. She writes, “Because it won’t update, there’s always the red circle on it indicating that I need to update.”

The current version of Life Cycle is up to date (and well reviewed), but its compatibility list only includes iPhones. That shouldn’t be a problem most of the time. While many apps are designed to be “universal,” and work equally well on iPhones and iPads of any size, some are aimed just at the iPhone, and most of those work in a compatibility mode on an iPad that’s a sort of iPhone-shaped emulator.

It’s possible Life Cycle is part of a small number of iPhone-only apps that include features that limit it to only being installed on an iPhone. That typically includes elements like being able to place a phone call within the app.

The only thing I can think is that an earlier version of Life Cycle didn’t have a provision that kept it from working on an iPad and the updated version did. It’s worth contacting the company in a case like this to see if they have insight—it might even be unintentional on their part. (Carol isn’t alone: other people have found the same problem with this particular app.)

If you want to keep the current version running and not have the update badge appear for App Store? There’s no avoiding it. You either have to delete the app or cope with the badge.

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